Field of the Invention
The present invention relates to a power supply circuit and an apparatus including the circuit, and particularly relates to an apparatus detecting a failure.
Description of the Related Art
The technologies to detect the electrical state of a device driven by an apparatus and the state of the apparatus have been available. According to Japanese Patent Laid-Open No. 2007-62264 disclosing a recording apparatus including a recording head corresponding to the device, it is determined whether or not a failure occurs in the recording head. When the failure occurrence is determined, the operation of the recording apparatus is stopped and information about the failure occurrence is displayed.
According to Japanese Patent Laid-Open No. 2007-62264, a power supply circuit or a power source (e.g., a DC/DC converter) supplying the voltage of the recording head is started, a voltage is supplied to the recording head, and a check of the presence or absence of a failure is made. According to the above-described method, however, the failure detection is performed for the recording head at the same voltage level as that of the operation state so that the recording head, the power supply circuit, etc. may malfunction. Particularly, a sequence including the steps of starting the DC/DC converter at least once and supplying a predetermined voltage based on the premise that the recording head is in usual conditions is performed. Accordingly, when a problem occurs in the circuit or a power line, all kinds of elements that are provided in the circuit are subjected to a thermal stress and an electrical stress.